Fig. 5.
Ethanol induces a fourth open state distinguished by its long open time. Cell-attached recordings of 5-HT3A(QDA) receptor-mediated currents evoked by 100 μM 5-HT (right) in the absence (A) and presence (B) of 25 mM ethanol. Pipette potential was 80 mV. Exponential fits to channel open time histograms (left), data pooled from four patches, reveal three open states in the absence and four open states in the presence of ethanol (gray lines). Resolution of fits was limited to twice the rise time of the filter (0.3 ms).